岩矿测试
巖礦測試
암광측시
ROCK AND MINERAL ANALYSIS
2014年
6期
839-843
,共5页
钼矿石%聚乙烯粉%粉末压片制样%波长色散X射线荧光光谱法
鉬礦石%聚乙烯粉%粉末壓片製樣%波長色散X射線熒光光譜法
목광석%취을희분%분말압편제양%파장색산X사선형광광보법
molybdenite%polyethylene powder%powder pelleting perpetration%X-ray Fluorescent Spectrometry
X射线荧光光谱（XRF）分析中，采用粉末压片制样存在粒度效应和矿物效应等问题，但当样品在一定的粒度、压制压力及压制时间条件下，矿物效应和粒度效应仅仅对钠、钙等轻元素的测试有影响，而对钼、铜、铅等元素的测试并无影响。基于此，本文建立了粉末压片制样波长色散XRF直接测定钼矿石中Mo、W、Cu、Pb、Zn、F、S、As、Bi等9种元素的方法。采用价格低廉的低压聚乙烯粉作衬垫镶边材料，样品在35 t的压力下压制30 s，制备的样片坚固光滑、吸潮性小，长期保存不发生形变，消除了粒度效应。选用自制的钼含量呈梯度变化的钼矿石样品及钼矿石、钨矿石、铜矿石、铅矿石、铋矿石、锌矿石等国家标准物质作为校准样品建立标准曲线，降低了矿物效应，采用经验系数法消除谱线重叠干扰和基体干扰。本方法的相对标准偏差小于2．1％，各元素的测定结果与电感耦合等离子发射光谱法等其他方法测量值吻合。与已报道的玻璃熔融和粉末压片制样方法相比较，检出限较低，如钼的检出限为3．67μg／g，比玻璃熔融法的检出限（450μg／g 或24μg／g）要低得多；砷的检出限为1．13μg／g，低于其他粉末压片法的检出限（7．8μg／g）。本方法有利于XRF法应用于定量分析基体组成复杂的钼矿石。
X射線熒光光譜（XRF）分析中，採用粉末壓片製樣存在粒度效應和礦物效應等問題，但噹樣品在一定的粒度、壓製壓力及壓製時間條件下，礦物效應和粒度效應僅僅對鈉、鈣等輕元素的測試有影響，而對鉬、銅、鉛等元素的測試併無影響。基于此，本文建立瞭粉末壓片製樣波長色散XRF直接測定鉬礦石中Mo、W、Cu、Pb、Zn、F、S、As、Bi等9種元素的方法。採用價格低廉的低壓聚乙烯粉作襯墊鑲邊材料，樣品在35 t的壓力下壓製30 s，製備的樣片堅固光滑、吸潮性小，長期保存不髮生形變，消除瞭粒度效應。選用自製的鉬含量呈梯度變化的鉬礦石樣品及鉬礦石、鎢礦石、銅礦石、鉛礦石、鉍礦石、鋅礦石等國傢標準物質作為校準樣品建立標準麯線，降低瞭礦物效應，採用經驗繫數法消除譜線重疊榦擾和基體榦擾。本方法的相對標準偏差小于2．1％，各元素的測定結果與電感耦閤等離子髮射光譜法等其他方法測量值吻閤。與已報道的玻璃鎔融和粉末壓片製樣方法相比較，檢齣限較低，如鉬的檢齣限為3．67μg／g，比玻璃鎔融法的檢齣限（450μg／g 或24μg／g）要低得多；砷的檢齣限為1．13μg／g，低于其他粉末壓片法的檢齣限（7．8μg／g）。本方法有利于XRF法應用于定量分析基體組成複雜的鉬礦石。
X사선형광광보（XRF）분석중，채용분말압편제양존재립도효응화광물효응등문제，단당양품재일정적립도、압제압력급압제시간조건하，광물효응화립도효응부부대납、개등경원소적측시유영향，이대목、동、연등원소적측시병무영향。기우차，본문건립료분말압편제양파장색산XRF직접측정목광석중Mo、W、Cu、Pb、Zn、F、S、As、Bi등9충원소적방법。채용개격저렴적저압취을희분작츤점양변재료，양품재35 t적압력하압제30 s，제비적양편견고광활、흡조성소，장기보존불발생형변，소제료립도효응。선용자제적목함량정제도변화적목광석양품급목광석、오광석、동광석、연광석、필광석、자광석등국가표준물질작위교준양품건립표준곡선，강저료광물효응，채용경험계수법소제보선중첩간우화기체간우。본방법적상대표준편차소우2．1％，각원소적측정결과여전감우합등리자발사광보법등기타방법측량치문합。여이보도적파리용융화분말압편제양방법상비교，검출한교저，여목적검출한위3．67μg／g，비파리용융법적검출한（450μg／g 혹24μg／g）요저득다；신적검출한위1．13μg／g，저우기타분말압편법적검출한（7．8μg／g）。본방법유리우XRF법응용우정량분석기체조성복잡적목광석。
In X-ray Fluorescent Spectrometric (XRF ) analysis,particle size effect and the matrix effect were reported when the powder pelleting preparation method was used.However,under certain particle size,tableting time and pressure,the effects existed only for light metals such as Na and Ca rather than heavy metal such as Mo, Cu and Pb.Based on these findings,an optimized powder pelleting sample preparation method for reducing particle size effect and other interferences was established for simultaneous determination of Mo,W,Cu,Pb,Zn,F,S,As and Bi in molybdenum ore samples by XRF.Low pressure polyethylene powder was used as the liner material to reduce cost;the sample powder was pelleted under 30 t pressures for 30 s.The prepared pellet was smooth with low moisture adsorption and could be stored for long periods without shape change.Particle size effect and matrix effect were diminished after calibration with national sulfide ore reference materials.An empirical coefficient was applied to reduce the influence of spectrum overlap and matrix interferences.The method precision (RSD)was <2.1%, and the results were consistent with those obtained by other analytical methods.Compared with the fusion sample preparation method,the optimized powder pelleting method demonstrates a lower detection limit.The detection limit for Mo was 3.67 μg/g vs.450 or 24 μg/g by the fusion method,and 1 .1 3 μg/g for As vs.7.8 μg/g by the normal powder pelleting method.
